1. April 12, 2012
Shale Gas Extraction

2. The Utica and Marcellus Plays
Utica and Marcellus Shale are in the Appalachian Basin
Currently ~14,000 active gas wells in NY State

3. Relative & Approximate Depth

4. Drilling
Not inconsequential effort 6 acre pad is typical. Drill cuttings, water storage ponds, etc.

5. Typical Gas Well X-Section
Multiple Layers of
Steel Casing and Cement Grout

6. Vertical & Horizontal Drilling
Well typically drilled vertically to 500 above Marcellus Shale
Curve from vertical to horizontal approximately 1,200 linear feet
Continues horizontally for several thousand feet
Final casing string cemented in place at end of well bore
Approximately 15 to 30 days required to drill a horizontal Marcellus well
Example illustrates 7,000 depth to shale (Typical for Pennsylvania)

7. Multiple Wells from a Single Pad
Line = 1,000 feet

8. Hydraulic Fracturing
Intensive 24-hour operation, typically taking place over several days to stimulate the entire horizontal wellbore.
High-volume fracturing used for horizontal well development
Process begins by perforating casing, cement and shale with perforating gun
Charge from gun opens fissures in shale to release natural gas, sand necessary to expand and prop open fissures
Water & additives injected under high pressure to carry sand into fractures

9. Hydraulic Fracturing Perforate the well casing & grout in sections
Pressure & Volume highly dependent upon local geology
Proppant (typically sand) keeps the fractures open

10. Hydraulic Fracturing
20% – 30% returns as “Flow-back” water within a few days; “produced water” follows Recycling or T&D Pennsylvania AMD Re-use??
> 1.2 Million wells hydraulically fractured in the US since 1949
“Typical” Fracture Fluid
~ 99.5% Water & Sand
Remaining ~0.5%
Surfactant
Gelling Agent
Friction Reducers
Acid
Biocide & Others
500,0000 to 4.0M gallons water/Marcellus well

11. Water Consumption 5,930 Millions of Gallons per Day 1,680 1,550 268
6,000
5,000
4,000
3,000
2,000
1,000
Power generation
Industrial
Public Water systems
Other
Mining
Marcellus Shale Drilling
182 60
Millions of Gallons per Day